If the side clip (A) will be reinstalled, scrape off the remaining double-sided adhesive tape from the clip, and clean the clip surface with isopropyl alcohol. Then attach the new double-sided adhesive tape (B) to the clip.
Install the side clips (A, B, C) on the side sill panel (D). Peel off the adhesive backing from the double-sided adhesive tape on the side clip (A).
Hold the panel up, and fit all the side clips into the holes in the body, then push on the panel until the clips snap into place.